xref: /linux/fs/ocfs2/cluster/tcp_internal.h (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * Copyright (C) 2005 Oracle.  All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public
17  * License along with this program; if not, write to the
18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19  * Boston, MA 021110-1307, USA.
20  */
21 
22 #ifndef O2CLUSTER_TCP_INTERNAL_H
23 #define O2CLUSTER_TCP_INTERNAL_H
24 
25 #define O2NET_MSG_MAGIC           ((u16)0xfa55)
26 #define O2NET_MSG_STATUS_MAGIC    ((u16)0xfa56)
27 #define O2NET_MSG_KEEP_REQ_MAGIC  ((u16)0xfa57)
28 #define O2NET_MSG_KEEP_RESP_MAGIC ((u16)0xfa58)
29 
30 /* we're delaying our quorum decision so that heartbeat will have timed
31  * out truly dead nodes by the time we come around to making decisions
32  * on their number */
33 #define O2NET_QUORUM_DELAY_MS	((o2hb_dead_threshold + 2) * O2HB_REGION_TIMEOUT_MS)
34 
35 /*
36  * This version number represents quite a lot, unfortunately.  It not
37  * only represents the raw network message protocol on the wire but also
38  * locking semantics of the file system using the protocol.  It should
39  * be somewhere else, I'm sure, but right now it isn't.
40  *
41  * New in version 7:
42  * 	- DLM join domain includes the live nodemap
43  *
44  * New in version 6:
45  * 	- DLM lockres remote refcount fixes.
46  *
47  * New in version 5:
48  * 	- Network timeout checking protocol
49  *
50  * New in version 4:
51  * 	- Remove i_generation from lock names for better stat performance.
52  *
53  * New in version 3:
54  * 	- Replace dentry votes with a cluster lock
55  *
56  * New in version 2:
57  * 	- full 64 bit i_size in the metadata lock lvbs
58  * 	- introduction of "rw" lock and pushing meta/data locking down
59  */
60 #define O2NET_PROTOCOL_VERSION 7ULL
61 struct o2net_handshake {
62 	__be64	protocol_version;
63 	__be64	connector_id;
64 	__be32  o2hb_heartbeat_timeout_ms;
65 	__be32  o2net_idle_timeout_ms;
66 	__be32  o2net_keepalive_delay_ms;
67 	__be32  o2net_reconnect_delay_ms;
68 };
69 
70 struct o2net_node {
71 	/* this is never called from int/bh */
72 	spinlock_t			nn_lock;
73 
74 	/* set the moment an sc is allocated and a connect is started */
75 	struct o2net_sock_container	*nn_sc;
76 	/* _valid is only set after the handshake passes and tx can happen */
77 	unsigned			nn_sc_valid:1;
78 	/* if this is set tx just returns it */
79 	int				nn_persistent_error;
80 
81 	/* threads waiting for an sc to arrive wait on the wq for generation
82 	 * to increase.  it is increased when a connecting socket succeeds
83 	 * or fails or when an accepted socket is attached. */
84 	wait_queue_head_t		nn_sc_wq;
85 
86 	struct idr			nn_status_idr;
87 	struct list_head		nn_status_list;
88 
89 	/* connects are attempted from when heartbeat comes up until either hb
90 	 * goes down, the node is unconfigured, no connect attempts succeed
91 	 * before O2NET_CONN_IDLE_DELAY, or a connect succeeds.  connect_work
92 	 * is queued from set_nn_state both from hb up and from itself if a
93 	 * connect attempt fails and so can be self-arming.  shutdown is
94 	 * careful to first mark the nn such that no connects will be attempted
95 	 * before canceling delayed connect work and flushing the queue. */
96 	struct delayed_work		nn_connect_work;
97 	unsigned long			nn_last_connect_attempt;
98 
99 	/* this is queued as nodes come up and is canceled when a connection is
100 	 * established.  this expiring gives up on the node and errors out
101 	 * transmits */
102 	struct delayed_work		nn_connect_expired;
103 
104 	/* after we give up on a socket we wait a while before deciding
105 	 * that it is still heartbeating and that we should do some
106 	 * quorum work */
107 	struct delayed_work		nn_still_up;
108 };
109 
110 struct o2net_sock_container {
111 	struct kref		sc_kref;
112 	/* the next two are vaild for the life time of the sc */
113 	struct socket		*sc_sock;
114 	struct o2nm_node	*sc_node;
115 
116 	/* all of these sc work structs hold refs on the sc while they are
117 	 * queued.  they should not be able to ref a freed sc.  the teardown
118 	 * race is with o2net_wq destruction in o2net_stop_listening() */
119 
120 	/* rx and connect work are generated from socket callbacks.  sc
121 	 * shutdown removes the callbacks and then flushes the work queue */
122 	struct work_struct	sc_rx_work;
123 	struct work_struct	sc_connect_work;
124 	/* shutdown work is triggered in two ways.  the simple way is
125 	 * for a code path calls ensure_shutdown which gets a lock, removes
126 	 * the sc from the nn, and queues the work.  in this case the
127 	 * work is single-shot.  the work is also queued from a sock
128 	 * callback, though, and in this case the work will find the sc
129 	 * still on the nn and will call ensure_shutdown itself.. this
130 	 * ends up triggering the shutdown work again, though nothing
131 	 * will be done in that second iteration.  so work queue teardown
132 	 * has to be careful to remove the sc from the nn before waiting
133 	 * on the work queue so that the shutdown work doesn't remove the
134 	 * sc and rearm itself.
135 	 */
136 	struct work_struct	sc_shutdown_work;
137 
138 	struct timer_list	sc_idle_timeout;
139 	struct delayed_work	sc_keepalive_work;
140 
141 	unsigned		sc_handshake_ok:1;
142 
143 	struct page 		*sc_page;
144 	size_t			sc_page_off;
145 
146 	/* original handlers for the sockets */
147 	void			(*sc_state_change)(struct sock *sk);
148 	void			(*sc_data_ready)(struct sock *sk, int bytes);
149 
150 	struct timeval 		sc_tv_timer;
151 	struct timeval 		sc_tv_data_ready;
152 	struct timeval 		sc_tv_advance_start;
153 	struct timeval 		sc_tv_advance_stop;
154 	struct timeval 		sc_tv_func_start;
155 	struct timeval 		sc_tv_func_stop;
156 	u32			sc_msg_key;
157 	u16			sc_msg_type;
158 
159 	struct mutex		sc_send_lock;
160 };
161 
162 struct o2net_msg_handler {
163 	struct rb_node		nh_node;
164 	u32			nh_max_len;
165 	u32			nh_msg_type;
166 	u32			nh_key;
167 	o2net_msg_handler_func	*nh_func;
168 	o2net_msg_handler_func	*nh_func_data;
169 	o2net_post_msg_handler_func
170 				*nh_post_func;
171 	struct kref		nh_kref;
172 	struct list_head	nh_unregister_item;
173 };
174 
175 enum o2net_system_error {
176 	O2NET_ERR_NONE = 0,
177 	O2NET_ERR_NO_HNDLR,
178 	O2NET_ERR_OVERFLOW,
179 	O2NET_ERR_DIED,
180 	O2NET_ERR_MAX
181 };
182 
183 struct o2net_status_wait {
184 	enum o2net_system_error	ns_sys_status;
185 	s32			ns_status;
186 	int			ns_id;
187 	wait_queue_head_t	ns_wq;
188 	struct list_head	ns_node_item;
189 };
190 
191 #endif /* O2CLUSTER_TCP_INTERNAL_H */
192